Trypanosoma cruzi infection reduces the population fitness of Mepraia spinolai, a Chagas disease vector.

The hematophagous insect Mepraia spinolai (Hemiptera: Reduviidae: Triatominae) is naturally infected with the protozoan parasite Trypanosoma cruzi, the agent of Chagas disease in humans. In this study, we compared the demographic parameters of M. spinolai with and without T. cruzi infection. We collected the immature life table data of 479 M. spinolai individuals of control cohort (reared on mice without T. cruzi infection) and 563 M. spinolai individuals of treatment cohort (reared on mice with T. cruzi infection). Nymphs were maintained in individual compartments inside a growth chamber (26°C; 65-75%) until adult emergence; moulting and survival were recorded daily. For the adult life table study of the control, we used 24 pairs of adults from the control cohort. For the adult life table study of T. cruzi-infected cohort, 25 infected females were paired with 25 males from the control cohort. Life table data were analysed using bootstrap-match technique based on the age-stage, two-sex life table. The preadult survival rate (0.5282) of the control cohort was significantly higher than that of the infected cohort (0.2913). However, the mean fecundity of reproductive females (Fr = 22.29 eggs/♀) and net reproductive rate of population (R0 = 5.07 offspring/individual) of the 0.5th percentile bootstrap-match control cohort were not significantly different from those of the infected cohort (Fr = 23.35 eggs/♀, R0 = 3.77 offspring/individual). Due to the shorter total preoviposition period and higher proportion of reproductive female, the intrinsic rate of increase (r = 0.0053 d-1 ) and finite rate of increase (λ = 1.0053 d-1 ) of control cohort of M. spinolai were significantly higher than those of the T. cruzi-infected cohort (r = 0.0035 d-1 , λ = 1.0035 d-1 ). These results suggest that T. cruzi infection reduces the population fitness of the Chagas disease vector M. spinolai.

First report of Rhodnius stali Lent, Jurberg & Galvão, 1993 (Hemiptera: Reduviidae: Triatominae), vector of Trypanosoma cruzi (TcI) and Trypanosoma rangeli (TrA), in Rondônia, Southwestern Brazilian Amazonia.

Triatomines are hematophagous insects of epidemiological importance as they are vectors of Chagas disease. The first report of Rhodnius stali Lent, Jurberg & Galvão, 1993 in Rondônia, Brazil, is described. The insects were captured on palm trees of the genus Oenocarpus sp. Two adult male specimens of R. stali were identified and were found to be infected with Trypanosoma cruzi and Trypanosoma rangeli. The confirmation of this Rhodnius species in Rondônia increases the number of triatomines from nine to ten species in this state.

Current Status of Omics Studies Elucidating the Features of Reproductive Biology in Blood-Feeding Insects.

Female insects belonging to the genera Anopheles, Aedes, Glossina, and Rhodnius account for the majority of global vector-borne disease mortality. In response to mating, these female insects undergo several molecular, physiological, and behavioral changes. Studying the dynamic post-mating molecular responses in these insects that transmit human diseases can lead to the identification of potential targets for the development of novel vector control methods. With the continued advancements in bioinformatics tools, we now have the capability to delve into various physiological processes in these insects. Here, we discuss the availability of multiple datasets describing the reproductive physiology of the common blood-feeding insects at the molecular level. Additionally, we compare the male-derived triggers transferred during mating to females, examining both shared and species-specific factors. These triggers initiate post-mating genetic responses in female vectors, affecting not only their reproductive success but also disease transmission.

An increased number of individuals of a potential host facilitates non-photic synchronisation in the haematophagous insect Triatoma infestans

BACKGROUND Triatoma infestans (Kissing bug) is the main vector of the parasite causative of Chagas disease in Latin-America. This species shows clear activity rhythms easily synchronised to day-night cycles (photic cycle). The haematophagous nature of these insects lead us to think that they may temporally adapt to the particular activity rhythms of potential hosts (non-photic cycle). Our previous data showed that kissing bugs were weakly affected by the activity-inactivity rhythm of a single host. OBJETIVE To determine if by increasing the number of individuals of a potential host, T. infestans could increase the likelihood of synchronisation. METHODS Individual activity rhythms of experimental insects, maintained in constant darkness in light-tight cabinets, localised in a room with 24 rodents, were continuously monitored. Another insect group that served as control was maintained in the same conditions but in a room without rodents. FINDINGS Most of the experimental insects synchronised, expressing a 24 h period coincident with the activity-inactivity rhythms of the rodents, while the controls free ran with a period significantly longer than 24 h. CONCLUSION Analogous to what happens with high vs low light intensity in photic synchronisers, a high number of rodents, in contrast to the previous one-rodent experiment, increased the potency of this non-photic zeitgeber.

Genetic diversity in peridomiciliary populations of Triatoma mexicana (Hemiptera: Reduviidae: Triatominae) in central Mexico.

Triatoma mexicana is an important vector of Trypanosoma cruzi-the etiological agent of Chagas disease. This triatomine species occurs in central Mexico, but little is known about its genetic variability. Using Cyt-b gene as a genetic marker, in this study, we determined the population genetic structure of T. mexicana collected from the States of Hidalgo, Guanajuato, and Queretaro where populations are largely peridomiciliary. A Bayesian approach was performed for the design of phylogenies, median-joining networks, and clustering among populations of T. mexicana. Our results show that the Hidalgo population was the most distinct, with the highest genetic and haplotypic variation (Hd = 0.963, π = 0.06129, and ɵ = 0.05469). Moderate gene flow (Nm) was determined among populations of Hidalgo and Queretaro. Populations from the three states showed differentiation (FST) values ranging from 0.22 to 0.3, suggesting an important genetic differentiation. The phylogenetic analysis showed the presence of five well-defined groups, as well as the haplotype network, where 24 haplotypes were observed forming five haplogroups with high mutational steps among them: 68 (Hgo-W2), 26 (Qto), 59 (Hgo-M), 44 (Hgo-W1), and 46 (Gto). Genetic isolation was apparently inferred in the Guanajuato population; however, the Mantel test did not show correlation between genetic (FST) and geographic (km) distances (p = 0.05). The STRUCTURE analyses showed seven genetic clusters and it was observed that a single cluster predominates in each sampled location. However, genetic admixture was detected in four localities. Our results show evidence that there are multiple species within the collected sampling area.

First report of Rhodnius montenegrensis (Hemiptera: Reduviidae: Triatominae) in Bolivia

ABSTRACT Background: The subfamily Triatominae, which comprises 157 species, carries the protozoan Trypanosoma cruzi, the etiological agent of Chagas disease. This short communication reports for the first time the occurrence of Rhodnius montenegrensis in Bolivia. Methods: Active searches were carried out on palm trees of the genus Oenocarpus in Beni district, Bolivia. Results: Fifteen R. montenegrensis specimens were collected from a rural area of the Beni district, Bolivia, and tested positive for T. cruzi. Conclusions: This new report expands the geographic distribution of the species in Latin America. Due to their ability to transmit trypanosomatids, the species deserves the attention of vector control programs.

Diatomaceous Earth for Arthropod Pest Control: Back to the Future.

Nowadays, we are tackling various issues related to the overuse of synthetic insecticides. Growing concerns about biodiversity, animal and human welfare, and food security are pushing agriculture toward a more sustainable approach, and research is moving in this direction, looking for environmentally friendly alternatives to be adopted in Integrated Pest Management (IPM) protocols. In this regard, inert dusts, especially diatomaceous earths (DEs), hold a significant promise to prevent and control a wide range of arthropod pests. DEs are a type of naturally occurring soft siliceous sedimentary rock, consisting of the fossilized exoskeleton of unicellular algae, which are called diatoms. Mainly adopted for the control of stored product pests, DEs have found also their use against some household insects living in a dry environment, such as bed bugs, or insects of agricultural interest. In this article, we reported a comprehensive review of the use of DEs against different arthropod pest taxa, such as Acarina, Blattodea, Coleoptera, Diptera, Hemiptera, Hymenoptera, Ixodida, Lepidoptera, when applied either alone or in combination with other techniques. The mechanisms of action of DEs, their real-world applications, and challenges related to their adoption in IPM programs are critically reported.

Impact of involving the community in entomological surveillance of Triatoma infestans (Klug, 1834) (Hemiptera, Triatominae) vectorial control.

BACKGROUND: Vectorial transmission is the principal path of infection by Trypanosoma cruzi, the parasite that causes Chagas disease. In Argentina, Triatoma infestans is the principal vector; therefore, vector control is the main strategy for the prevention of this illness. The Provincial Program of Chagas La Rioja (PPCHLR) carries out entomological evaluation of domiciliary units (DUs) and spraying of those where T. infestans is found. The lack of government funds has led to low visitation frequency by the PPCHLR, especially in areas with a low infestation rate, which are not prioritized. Therefore, seeking possible alternatives to complement control activities is necessary. Involving householders in entomological evaluation could be a control alternative. The major objective was to determine the cost of entomological evaluation with and without community participation. METHODS: For entomological evaluation without community participation, PPCHLR data collected in February 2017 over 359 DUs of the Castro Barros Department (CBD) were used. For entomological evaluation with community participation, 434 DUs of the same department were selected in November 2017. Each householder was trained in collecting insects, which were kept in labeled plastic bags, recovered after 2 weeks, and analyzed in the laboratory for the presence of T. cruzi. Using householders' collection data, a spatial scan statistic was used to detect clusters of different T. infestans infestations. Entomological evaluation costs with and without community participation related to the numbers of DUs visited, DUs evaluated, and DUs sprayed were calculated and compared between methodologies. In addition, the number of DUs evaluated of the DUs visited was compared. RESULTS: According to the results, the triatomines did not show evidence of T. cruzi infection. Spatial analysis detected heterogeneity of T. infestans infestation in the area. Costs related to the DUs visited, evaluated, and sprayed were lower with community participation (p < 0.05). In addition, more DUs were evaluated in relation to those visited and a greater surface area was covered with community participation. CONCLUSION: Participation of the community in the infestation survey is an efficient complement to vertical control, allowing the spraying to be focused on infested houses and thus reducing the PPCHLR's costs and intervention times.

Susceptibility dynamics between five Trypanosoma cruzi strains and three triatomine (Hemiptera: Reduviidae) species.

American trypanosomiasis is a zoonosis caused by the parasite Trypanosoma cruzi and is transmitted mainly by blood-sucking insects belonging to the subfamily Triatominae. The importance of this parasite lies in its wide geographical distribution, high morbidity, and the fact that there has not yet been an effective treatment or vaccine. Previous studies have detailed the interactions between different triatomine species and T. cruzi strains. However, the factors necessary to establish infection in triatomines have not yet been fully elucidated. Furthermore, it is postulated that the coexistence between the parasite and triatomines could modulate the susceptibility to infection in these insects. Accordingly, in this study, we evaluated the susceptibility to T. cruzi infection in the species Triatoma (Meccus) pallidipennis, Triatoma barberi, and Triatoma lecticularia, which were infected with Ninoa, H8, INC-5, Sontecomapan, and Hueypoxtla strains. The criteria used to establish susceptibility were the amount of blood ingested by the insects, percentage of infected triatomines, concentration of parasites in feces, and percentage of metacyclic trypomastigotes in feces. These parameters were analyzed by fresh examination and differential count with Giemsa-stained smears. Our main findings suggest the following order of susceptibility concerning infection with T. cruzi: T. lecticularia > T. barberi > T. (Meccus) pallidipennis. Furthermore, the study concludes that an increased susceptibility to infection of triatomines that share the same geographic region with different strains of T. cruzi is not always a fact.

First report of Microtriatoma borbai Lent & Wygodzinsky, 1979 (Hemiptera, Reduviidae, Triatominae) in the state of Espírito Santo, Brazil: would M. borbai be living in eucalyptus crops?

Abstract INTRODUCTION: The occurrence of Microtriatoma borbai in the state of Espírito Santo, Brazil is reported by the first time. METHODS: A triatomine specimen collected in a hybrid eucalyptus crop in the municipality of Aracruz, Espírito Santo state was found to be a male M. borbai. RESULTS: This finding expands the geographical distribution of M. borbai from four to five Brazilian states. It is the first report of M. borbai occurrence inside a eucalyptus crop. CONCLUSIONS: The occurrence of M. borbai in the state of Espírito Santo broadens the geographical distribution of this species in southeastern Brazil.

First report of Microtriatoma borbai Lent & Wygodzinsky, 1979 (Hemiptera, Reduviidae, Triatominae) in the state of Espírito Santo, Brazil: would M. borbai be living in eucalyptus crops?

Abstract INTRODUCTION: The occurrence of Microtriatoma borbai in the state of Espírito Santo, Brazil is reported by the first time. METHODS: A triatomine specimen collected in a hybrid eucalyptus crop in the municipality of Aracruz, Espírito Santo state was found to be a male M. borbai. RESULTS: This finding expands the geographical distribution of M. borbai from four to five Brazilian states. It is the first report of M. borbai occurrence inside a eucalyptus crop. CONCLUSIONS: The occurrence of M. borbai in the state of Espírito Santo broadens the geographical distribution of this species in southeastern Brazil.

Psammolestes tertius Lent & Jurberg, 1965 (Hemiptera, Reduviidae, Triatominae): first report in Sergipe State, Brazil

Abstract INTRODUCTION: This study reports the first occurrence of Psammolestes tertius (Hemiptera, Reduviidae, Triatominae) in the state of Sergipe, Brazil. METHODS: In 2020, 95 specimens were collected from the municipality of Porto da Folha, Sergipe, Brazil. RESULTS: This finding expands the geographical distribution of the species from 15 states in Brazil to 16 and increases the biodiversity of triatomines in the state of Sergipe. CONCLUSIONS: The presence of P. tertius in the state of Sergipe demonstrated a wider distribution of this species in northeastern Brazil.

List of the type specimens of Triatominae (Hemiptera: Heteroptera: Reduviidae) in the Hemimetabola Collection of the Museum für Naturkunde, Berlin.

The Hemimetabola Collection of the Museum für Naturkunde Berlin, Leibniz-Institut für Evolutions- und Biodiversitätsforschung, located in Berlin, Germany, holds types of 22 species of Triatominae (Hemiptera: Heteroptera: Reduviidae) belonging to six genera: Belminus Stål, 1859; Eratyrus Stål, 1859; Meccus Stål, 1859; Panstrongylus Berg, 1879; Rhodnius Stål, 1859; and Triatoma Laporte, 1832. We present a detailed list containing nomenclatural, taxonomic and label data, and photographs of specimens and their labels.

Trypanosoma cruzi infections and associated pathology in urban-dwelling Virginia opossums (Didelphis virginiana).

Trypanosoma cruzi, a zoonotic protozoan parasite, infects a wide range of mammals. The southern United States has endemic sylvatic transmission cycles maintained by several species of wildlife and domestic dogs. We hypothesized that urban-dwelling opossums (Didelphis virginiana) in South Texas are infected with T. cruzi, and that tissue pathology would be associated with infection. In 2017, we collected blood, heart tissue and anal gland secretions from 100 wild opossums across three seasons that were trapped by animal control in South Texas. In addition, anal gland tissue and intercostal muscle were collected from 43 of the 100 opossums for which time allowed the extra tissue collection. All blood, tissue, and secretion samples were screened for T. cruzi DNA using qPCR with confirmation of positive status achieved through one or more additional PCR assays, including a qPCR to determine the parasite discrete typing unit (DTU). T. cruzi DNA was detected in at least one tissue of 15% of the opossums sampled: blood clot (9%), heart tissue (10%), anal gland secretions (12%), intercostal muscle (16.3%), and anal gland tissue (11.6%). Infection was detected in two or more different tissue types in nine of the opossums. The 35 tissues for which parasite DTU was determined were exclusively 'Tcl'- a DTU previously associated with locally-acquired human disease in the United States. T. cruzi-positive opossums were nearly 14 times more likely to exhibit significant heart lesions on histopathology (lympoplasmacytic inflammation±fibrosis) when compared to negative opossums (OR = 13.56, CI = 1.23-751.28, p-value = 0.03). Three triatomines were opportunistically collected from the study site, of which two were infected (66.7%), and bloodmeal analysis revealed canine, opossum, and human bloodmeals. Given the presence of parasite in opossum blood, unique potential for shedding of parasite in anal glad secretions, and evidence of vectors feeding on opossums, it is likely that opossums serve as wild reservoirs around urban dwellings in South Texas.

Transcriptomics supports local sensory regulation in the antenna of the kissing-bug Rhodnius prolixus.

BACKGROUND: Rhodnius prolixus has become a model for revealing the molecular bases of insect sensory biology due to the publication of its genome and its well-characterized behavioural repertoire. Gene expression modulation underlies behaviour-triggering processes at peripheral and central levels. Still, the regulation of sensory-related gene transcription in sensory organs is poorly understood. Here we study the genetic bases of plasticity in antennal sensory function, using R. prolixus as an insect model. RESULTS: Antennal expression of neuromodulatory genes such as those coding for neuropeptides, neurohormones and their receptors was characterized in fifth instar larvae and female and male adults by means of RNA-Sequencing (RNA-Seq). New nuclear receptor and takeout gene sequences were identified for this species, as well as those of enzymes involved in the biosynthesis and processing of neuropeptides and biogenic amines. CONCLUSIONS: We report a broad repertoire of neuromodulatory and neuroendocrine-related genes expressed in the antennae of R. prolixus and suggest that they may serve as the local basis for modulation of sensory neuron physiology. Diverse neuropeptide precursor genes showed consistent expression in the antennae of all stages studied. Future studies should characterize the role of these modulatory components acting over antennal sensory processes to assess the relative contribution of peripheral and central regulatory systems on the plastic expression of insect behaviour.

Modulation of IMD, Toll, and Jak/STAT Immune Pathways Genes in the Fat Body of Rhodnius prolixus During Trypanosoma rangeli Infection.

Trypanosoma rangeli is the second most common American trypanosome that infects man. It is vectored by triatomines from the genus Rhodnius, in which it invades the hemolymph and infects the salivary glands, avoiding the bug immune responses. In insects, these responses are initiated by well conserved pathways, mainly the IMD, Toll, and Jak/STAT. We hypothesize that long-term infection with T. rangeli in the gut or hemolymph of Rhodnius prolixus triggers different systemic immune responses, which influence the number of parasites that survive inside the vector. Thus, we investigated groups of insects with infections in the gut and/or hemolymph, and evaluated the parasite load and the expression in the fat body of transcription factors (Rp-Relish, Rp-Dorsal, and Rp-STAT) and inhibitors (Rp-Cactus and Rp-Caspar) of the IMD, Toll, and Jak/STAT pathways. We detected lower parasite counts in the gut of insects without hemolymph infection, compared to hemolymph-infected groups. Besides, we measured higher parasite numbers in the gut of bugs that were first inoculated with T. rangeli and then fed on infected mice, compared with control insects, indicating that hemolymph infection increases parasite numbers in the gut. Interestingly, we observed that genes from the three immune pathways where differentially modulated, depending on the region parasites were present, as we found (1) Rp-Relish downregulated in gut-and/or-hemolymph-infected insects, compared with controls; (2) Rp-Cactus upregulated in gut-infected insect, compared with controls and gut-and-hemolymph-infected groups; and (3) Rp-STAT downregulated in all groups of hemolymph-infected insects. Finally, we uncovered negative correlations between parasite loads in the gut and Rp-Relish and Rp-Cactus expression, and between parasite counts in the hemolymph and Rp-Relish levels, suggesting an association between parasite numbers and the IMD and Toll pathways. Overall, our findings reveal new players in R. prolixus-T. rangeli interactions that could be key for the capacity of the bug to transmit the pathogen.

Kissing Bugs Harboring Trypanosoma cruzi, Frequently Bite Residents of the US Southwest But Do Not Cause Chagas Disease.

BACKGROUND: Kissing bugs are common household pests in the Desert Southwest of the United States. These hematophagous bugs enter homes and suck blood from resident humans and pets. They are vectors of Trypanosoma cruzi, an enzootic parasite in small mammals and the cause of Chagas disease in humans. Autochthonous cases of Chagas disease are rare in the United States despite the presence of the vector and parasite. Environmental and biological factors accounting for this phenomenon need studying. METHODS: Homeowners in Bisbee and Tucson, Arizona captured kissing bugs inside homes during 2017-2018. Bugs were tested for presence of T. cruzi by polymerase chain reaction. Residents bitten by kissing bugs were tested for Chagas disease by serology. We evaluated invaded homes in the 2 cities. RESULTS: Three species of kissing bugs (n = 521) were collected in or near homes. Triatoma rubida was the most common triatomine in Tucson; T. recurva in Bisbee. T. protracta was uncommon. Seventeen percent of bugs captured in Bisbee and 51.1% in Tucson harbored T. cruzi. Bite victims (n = 105) recalled more than 2200 bites. Reactions to bites were common, including 32 episodes of anaphylaxis in 11 people (10.5%). Tests for Chagas disease (n = 116) were negative. Median age of houses was 91 years in Bisbee and 7 years in Tucson. Bisbee houses had pier and beam foundations. Tucson houses were built on concrete slabs. CONCLUSIONS: Kissing bugs harboring T. cruzi readily entered new and old homes. Bites of humans caused severe, life-threatening reactions. There was no serological evidence of Chagas disease among those bitten.

Potential impact of climate change on the geographical distribution of two wild vectors of Chagas disease in Chile: Mepraia spinolai and Mepraia gajardoi.

BACKGROUND: Mepraia gajardoi and Mepraia spinolai are endemic triatomine vector species of Trypanosoma cruzi, a parasite that causes Chagas disease. These vectors inhabit arid, semiarid and Mediterranean areas of Chile. Mepraia gajardoi occurs from 18° to 25°S, and M. spinolai from 26° to 34°S. Even though both species are involved in T. cruzi transmission in the Pacific side of the Southern Cone of South America, no study has modelled their distributions at a regional scale. Therefore, the aim of this study is to estimate the potential geographical distribution of M. spinolai and M. gajardoi under current and future climate scenarios. METHODS: We used the Maxent algorithm to model the ecological niche of M. spinolai and M. gajardoi, estimating their potential distributions from current climate information and projecting their distributions to future climatic conditions under representative concentration pathways (RCP) 2.6, 4.5, 6.0 and 8.5 scenarios. Future predictions of suitability were constructed considering both higher and lower public health risk situations. RESULTS: The current potential distributions of both species were broader than their known ranges. For both species, climate change projections for 2070 in RCP 2.6, 4.5, 6.0 and 8.5 scenarios showed different results depending on the methodology used. The higher risk situation showed new suitable areas, but the lower risk situation modelled a net reduction in the future potential distribution areas of M. spinolai and M. gajardoi. CONCLUSIONS: The suitable areas for both species may be greater than currently known, generating new challenges in terms of vector control and prevention. Under future climate conditions, these species could modify their potential geographical range. Preventive measures to avoid accidental human vectorial transmission by wild vectors of T. cruzi become critical considering the uncertainty of future suitable areas projected in this study.

Triatomines: Trypanosomatids, Bacteria, and Viruses Potential Vectors?

Triatominae bugs are the vectors of Chagas disease, a major concern to public health especially in Latin America, where vector-borne Chagas disease has undergone resurgence due mainly to diminished triatomine control in many endemic municipalities. Although the majority of Triatominae species occurs in the Americas, species belonging to the genus Linshcosteus occur in India, and species belonging to the Triatoma rubrofasciata complex have been also identified in Africa, the Middle East, South-East Asia, and in the Western Pacific. Not all of Triatominae species have been found to be infected with Trypanosoma cruzi, but the possibility of establishing vector transmission to areas where Chagas disease was previously non-endemic has increased with global population mobility. Additionally, the worldwide distribution of triatomines is concerning, as they are able to enter in contact and harbor other pathogens, leading us to wonder if they would have competence and capacity to transmit them to humans during the bite or after successful blood feeding, spreading other infectious diseases. In this review, we searched the literature for infectious agents transmitted to humans by Triatominae. There are reports suggesting that triatomines may be competent vectors for pathogens such as Serratia marcescens, Bartonella, and Mycobacterium leprae, and that triatomine infection with other microrganisms may interfere with triatomine-T. cruzi interactions, altering their competence and possibly their capacity to transmit Chagas disease.

An updated and illustrated dichotomous key for the Chagas disease vectors of Triatomabrasiliensis species complex and their epidemiologic importance.

In the subfamily Triatominae, Triatoma exhibits the largest number of species, which are arranged in complexes. For the T.brasiliensis species complex, recent investigations based on results of geometric morphometrics combined with phylogeny have provided evidence that it should be composed of seven species: T.brasiliensis, T.bahiensis, T.juazeirensis, T.lenti, T.melanica, T.petrocchiae, and T.sherlocki, in which T.brasiliensis is divided in two subspecies: T.b.brasiliensis and T.b.macromelasoma. A taxonomic key is presented to identify each taxon. Among members of this complex, T.b.brasiliensis is the most important in an epidemiologic context, due to its high prevalence in natural infection by Trypanosomacruzi combined with a pronounced adaptation to domiciliary habitats. However, some members may be currently invading and colonizing homes, a process known as domiciliation. Therefore, the key presented here may be potentially useful for researchers as well as those involved in vector control measures.